End users (or their caretakers) sometimes, by mistake, switch right and left devices of a binaural hearing assistance system between the ears. Users may e.g. confuse which device should be placed on the right ear and which aid should be placed on the left ear. This is especially true with behind-the-ear (BTE) styles. The interchange may e.g. happen when a BTE-user removes and cleans the ear molds (e.g. daily) and then reattaches the BTE-parts to them.
In case of hearing assistance devices adapted for compensating a hearing loss of a user, this may create problems, because hearing losses of left and right ears seldom are completely symmetric. Since such asymmetry is typically reflected in the fitting of binaural systems, it is important to ensure that each of the two (dedicated) hearing assistance devices (e.g. including BTEs) is placed on the respective correct ear. Misplacement will result in incorrect amplification (‘bad fitting’). Depending on the differences in fitting, the mismatch may a) not be detected, b) clearly detected, or worse, c) detected as an irritation (without knowing its cause), which could lead to the perception that the hearing aids are of poor quality (and subsequent abandonment). Further, if a child receives incorrect amplification over a longer period of time due to a mismatch, this could lead to incorrect, delayed or difficult learning of speech.
Other problems related to location identification of hearing assistance devises may occur during a first time fitting. When making a first fitting of a new behind the ear instrument, the instrument itself does not know if it is put on the right and left ear. This is especially troublesome when using wireless communication between the ‘left’ and ‘right’ devices, since the fitting system then needs to acquire this information, e.g. through a special ‘instrument selection window’, which e.g. utilizes playback of tones in one of the instruments and detects the location of the active instrument. Since hearing losses are not prescribed in the hearing assistance devices at this time of the fitting process, an adjustment of the loudness of the tone may be necessary.
Today, a correct location of a hearing assistance device may be indicated by visually different labels or markers on the ‘left’ (e.g. indicated by a blue marker) and ‘right’ (e.g. indicated by a red marker) devices. For blind or visually impaired people and for people not knowing this color-code (e.g. substitutes in a nursery home or kindergarten teachers), such visual indication is insufficient to guarantee a correct placement. Also, for other users, the devices can be switched between ears by mistake.
WO2012044278A1 deals with a hearing instrument comprising means for actively identifying the hearing instrument as corresponding to a respective user's ear for which it was assigned.
US2008144867A1 deals with the correct assignment of the two hearing devices of a binaural hearing system to the ears or of the wearer during fitting.
Thus, there is a need for an improved (preferably automated) scheme for detecting whether a hearing assistance device is located as intended.